Electric switch



N. D. LEVIN ELECTRIC SWITCH oct. 2,1, 1930.

Filed Aug. '3, 1926 Patented Oct. 21, 1930 UNITED STATES PATENT OFFICENILS D, LEVIN, OF COLUMBUS, OI-IIO, ASSIG-NOR TO THE JEFFREYMANUFACTURING COMPANY, OF COLUMBUS, OHIO7 A CORPORATION 0F OHIO ELECTRICSWITCH Application led August 3, 1926.

The present invention relates to certain new and useful improvements inelectric switches of the type which is provided with means to localizeand minimize the effect of the arcsformed between the contact members ofthe switch when the current is interrupted.

The especial object is to provide a switch of the class described havinglarge carrying capacity and wherein the arcing caused by theinterruption of the current is localized to points not included in thecircuit during the maintenance of said circuit.

A further object is to provide in a switch of the class described,improved means to minimize the destructive effect of the arc upon thecontact elements of the switch.

These and other'objects will be fully set forth in the followingspecification and illustrated in the accompanying dra-wings of 2@ WhichFig. 1, is a plan view of a switch mechanism constructed in accordancewith my present invention, certain parts being broken away to revealother parts.

Fig. 2, is a sectional view taken along the lines II-I of Fig.` 1.

Like numerals refer to similar parts in both figures. Y

In application, Serial No. 105,873, lecl April 30, 1926, by Valter J.Bauroth, there is disclosed an explosion proof casing adapted to protectelectrical apparatus subject to the' production of electric arcs fromcontact with the explosive gas charged atmosphere of a coal mine. Forpurposes of illustration I have here shown a casing such as abovedescribed, in which is mounted two electric switches constructed inaccordance with my present invention7 operatively connected with thelocking lever of said casing, and electri cally connected with theconductors ofl an electric circuit, in such manner that when the casingis open for inspection or adjustment of its contents, both sides of saidcircuit will be disconnected from the source of electric supply, andsaid circuit may not be restored until the casing is closed and itscover locked in closed position. v

As shown in the drawings the numeral 1 refers to the casingand thenumeral 2 re- Serial No. 126,846.

fers to the disc by which the opening in the top of the casing may beclosed. The disc 2 is pivotally attached to the hinge member 3 by thepivot pin 4, and the hinge member 3 is rotatable about a hinge pin 5which is attached to the side wall of the casing by the lug 6.' The slot7 in the hinge member 3 allows sufficient movement of the hinge member 3transversely of the hinge pin 5 to permit the disc 2 to be moved G0directly outwardly of the casing by the screwing action when said discis rotated about the pivot pin 4. The locking levers 8 are pivotallymounted in suitable bearings formed in the end wall of the casing, and-these levers are joined togetherv by a cross bar 9 on which is mounteda roller adapted to engage the hinge member 3 when the levers 8 are intheir locked position, to thereby prevent the outward movement of saidhinge 7e member and the attached cover disc 2. In like manner theengagement of the roller 10 with the hinge member 3 will preventmovement of the locking leversS to their extreme forward, or lockedposition., until the cover 7 disc 2 has been screwed home to its closedposition.

Mounted within the casing 1 is an insulating base 11 upon which aremounted the electrical ydevices contained within the casing.

ttached to the insulating base 11 are the switches 12 and 13 positionedadjacent the ends of the casing, and each operatively connected with,but electrically insulated from the adjacent locking lever 8. As theseswitches are alike a description of one will apply to both.

Fixed to the insulating base 11 is a metallic supporting member 14connected in suitable manner through the conductor 15 with the source ofelectric supply. Formed in the supporting member 14 in alinement withthe axisv of the journal of the locking lever 8 is a journal bearing inwhich is mounted a hub 16 having radially extending arms 17 and 18 tothe extremities of which are attached contact segments 19 and 20 adaptedto engage with the contact brushes 21 and 22 respectively. The brushes21 and 22 are fixed to a supporting member 23 mounted 10c upon theinsulating base 11,v and electrically connected with the electricapparatus which is to be supplied with current through the conductor24e. The proportions of these parts are such that when the locking lever8 is in its extreme forward, or locking position, both of thecontactsegnients 19 and 2O will be in contact with their respectivebrushes 21 and 22,a nd when the locking lever 8 is in its vthe brush 22i"By this arrangement no arc is formed on the segment 20 and the arcformed on the segment 19 is removed from that part ofthe segment incontact with the brush 21 when the switch is fully closed.

To further minimize the ydestruct-ive eliect of the electric arc I havemounted adjacent the brush 21 a permanent horseshoe shaped magnet 25,the poles of which extend into proximity with said contact brush 19 soas tov maintain a magnetic field at the point where the 'circuit isfinally broken. The magnetic ield produced by this permanent magnet'tends to quickly extinguish the electric arcand thereby reduce itsinjurious effect upon the contact segment 22. Y

It is to be understood that the devices I V'above describe-d maybesubjectedto a wide variation as to detailwithout departure the spiritVor my invention. y What I claim is:

from

1. In a switch, a pair of spaced segmental contact elements, meanssupporting said elements for rotary movement about a common axi s,'abrush arranged 'tangentially to .the

fpath of'each 'or said Contact elements for cooperation with saidelements, 'a conductor in, connection with said Contact elements, aconductorin Ac'onnectijen with's'aid brushes, and

means to rotatesaid contact'elements to bring into' and .out or Contactwith said brushes, one 'of 'sai'dfcontact 4velements having anVextension arranged to makecontactiifirst 'and tobreak contact last.

Y. 2. In a switch, afpai'r yorfvspac'ed 'segmental' Contact elements,meanssupport'ing said eiements for rotary movement about a common "axis,brush arranged tangentially to the Vpath lofeachof said Contact elementsfor coin l'joirneiction with fsai'dcon'tat elements, a f conductor inconnection with said brushes,

vand means tofrotate 'said centactelenients to and to break Contactlast, the respective conductor being connected with said last namedcontact element Vat the supported portion of the latter.

3. In a switch, a pair of spaced segmental contact elements, radial armssupporting said elements for rotary movement about a common axis, a.brush arranged tangentially to the path of each ofsaidcontact elementsfor cooperation with said elements, a ccrid'uc'to'r in connection withsaid Contact elements, a conductor in connection with said brushes,

and means to rotate said contactrelements to Y bring them into and outor Contact with said brushes, one of said contact elements having anextension arranged to makev Contact irst vand to break contact last. 4.In a switch, a pair or spaced segmenta contact elements, radial armssupporting said elements in constantrelation to eachother for rotarymovement about a common axis, a brush arranged tangentially to the pathor each of said contact elements for cooperation with said elements, aconductor in connection with said contact elements, a conductor iiiconnection with said brushes, and means to rotate said contact elementsto bring them into and out of contactlwith vsaid brushes, one oi saidcontact elements having an vextension arranged to make'contact lirs'tand to break contact last.'

5. In a switch, a pair or spaced segmental contactelenie'nts, integralradial arms supporting said elementsin constant relation to eachotherfor rotary movement about a common axis, a' `brush arrangedtangentiallyto 'the path of each or said Contact elements forcooperation with said elements, al con ductor in connection with saidcontact elements,- aconduc'tor in connection with said brushes, andmeans to rotate said 'co'i'itactelements tobringV them into andy out orContact with said brivislies,` one of said contactel'einntsha'v'ing vanextension arranged to make contact irst'an'd to break VYContact last.

l 6. 'Inra switch, a pair of sp'acedsegmental contact elements, radialelectrically-conductive arms supporting said velements` for ro- VAtarymovement about a common axis, ai brush arranged` tangentially to thepathV of Yeach "of sa-id contact elements vforjc'c'ioperation''with vthelatter, a conductor in connection with said contact elements throughsaid arms, a conductor'in connection with said brushes,

and means to rotate 4said contact elements to lbring theminto and out"of contact Awith said brushes, one of said contact elements having yanextension arranged to make vContact `first andk to break contactlast.' c

V7. In a switch, a pair "of spacedjsegmental other, radialelectricallyl'conductive varms supporting said elements in`V constantrelation for rot ary 'movement about" a 4conirri'oi'i axis, a

lios

V4c'liitact elementsVV arranged one before the each of said Contactelements for cooperation With the latter, a conductor in connection Withsaid Contact elements through said arms, a conductor in connection withsaid brushes, and means to rotate said Contact elements to bring theminto and out of contact With said brushes, one of said Contact elementshaving an extension arranged to make Contact first and to break Contactlast.

In testimony whereof I have hereunto set my hand.

NILS D. LEVIN.

